1. Field of the Invention
The present invention relates to portable door alarms that connect to a door and more particularly to portable door alarms for indicating an unauthorized opening of a door.
2. Background Information
There are several types of devices developed for indicating the unauthorized entry into a residence or into a dorm room or hotel room or the like. While many alarms are built into the door or part of a larger security system, some devices have been developed that are portable and connect to a door or door jamb without harming the door. Some examples of portable door alarms include those found in patents such as U.S. Pat. No. 4,851,814, U.S. Pat. No. 6,154,130, U.S. Pat. No. 5,850,172, and U.S. Pat. No. 4,540,980. While these patented items and other systems may have useful features, there is room for improvement.